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Data Sheet TLE6284G H-Bridge Driver IC
* Compatible to very low ohmic normal Turn on current level input N-Channel MOSFETs Turn off current * PWM - DIR - Interface Supply voltage range * PWM frequency up to 50kHz Gate Voltage * Operates down to 7.5 V Temperature range supply voltage * Low EMC sensitivity and emission * Adjustable dead time with shoot through protection * Deactivation of dead time and shoot through protection possible * Short circuit protection for each Mosfet can be disabled and adjusted * Driver undervoltage shut down * Reverse polarity protection for the driver IC * Fast disable function / Inhibit for low quiescent current * Input with TTL characteristics * 2 bit diagnosis * Thermal overload warning for driver IC * Shoot through protection * Integrated bootstrap diodes
Features
Product Summary
IGxx(on) IGxx(off) VVs VGS TJ
850 580 7.5 ... 60 10 -40...+150
mA mA V V C
P-DSO-20
Application
* Dedicated for DC-brush high current motor bridges in PWM control mode for 12, 24 and 42V powernet applications. * The input structure allows an easy control of a DC-brush motor
General Description
H-bridge driver IC for MOSFET power stages with multiple protection functions. The TLE6184G is very similar to the TLE6281G. The major difference is that the Short Circuit protection level of the TLE6284G can be adjusted by external resistors or even disabled. The pin outs are different as well.
Block Diagram
VS GND Linear Regulator Charge Pump BH1 BH2
Floating HS Driver 1 + VGS limitation HS1 + Short circuit SCD detect. + Undervoltage Floating HS Driver 2 + VGS limitation HS2 + Short circuit SCD detect. + Undervoltage Floating LS Driver 1 + VGS limitation LS1 + Short circuit SCD detect. + Undervoltage Floating LS Driver 2 + VGS limitation LS2 + Short circuit SCD detect. + Undervoltage
DH1 GH1 SH1 DH2 GH2 SH2 DL1 GL1
INH
INH
HS1
PWM DIR
Input control
LS1 HS2
Level
Dead time DT/DIS
LS2
ER1
Undervoltage Short circuit Detect.
OR
Undervoltage HSx Undervoltage LSx
Shift
Short Circuit Detection
ER2
Overtemp. warning
Tj > 170oC typ.
DL2 GL2
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2006-01-30
Data Sheet TLE6284G
Application Block Diagram
Watchdog Reset Q
TLE 4278G
D
I
Vs = 12V
R = 10 Ohm CD = 47nF Cs = 47F
CQ 47F
Cs = 47F RQ 47kOhm RQ 47kOhm Cs = 1F
WD
R
Vcc ER1 ER2 INH
68 kOhm
BCR192W
Vs
BH1 DH1 GH1 SH1 BH2 DH2
RSCD
CB 220nF RSCD
CB 220nF
RSCD
C
RQ 10kOhm
DT / DIS
RINH 220k
GH2 SH2
RSCD
M
PWM
RSCD1
DL1 GL1
DIR
RSCD3
DL2 GL2
RSCD2 RSCD4
GND
This application block diagram shows one of the possibilities to use this Driver IC. The voltage devider networks accross the 4 MOSFETs (resistors RSCD) allow to increas the current limit threshold for Short Circuit protection. The RSCD resistors also provide a charge path for the bootstrap capacitors. If RSCD resistors are not used in the application, a 12k Ohm resistor should be introduced between SH1 to GND and SH2 to GND. 2 2006-01-30
Data Sheet TLE6284G
DT/DIS ER1 DIR PWM DL2 ER2 GND VS DL1 INH
1 2 3 4 5 6 7 8 9 10 10
20 19 18 17
GL2 SH2 GH2 BH2 DH2 DH1 BH1 GH1 SH1 GL1
TLE6284G
16 15 14 13 12 11
Pin 1
Symbol DT / DIS
Function a) Set adjustable dead time by external resistor b) Reset ERx register c) Disable output stages
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
ER1 DIR PWM DL2 ER2 GND VS DL1 INH GL1 SH1 GH1 BH1 DH1 DH2 BH2 GH2 SH2 GL2
Error flag for driver shut down Control input for spinning direction of the motor Control input for PWM frequency and duty cycle Sense contact for short circuit detection low side 2 Warning flag Temperature / distinguish if short circuit or undervoltage lock out occured Logic Ground Voltage supply Sense contact for short circuit detection low side 1 Sets complete device to sleep mode to achieve low quiescent currents Output to gate low side switch 1 Connection to source high side switch 1 Output to gate high side switch 1 Bootstrap supply high side switch 1 Sense contact for short circuit detection high side 1 Sense contact for short circuit detection high side 2 Bootstrap supply high side switch 2 Output to gate high side switch 2 Connection to source high side switch 2 Output to gate low side switch 2
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Data Sheet TLE6284G
Maximum Ratings at Tj=-40...+150C unless specified otherwise Parameter Supply voltage 1 Operating temperature range Storage temperature range Max. voltage range at PWM, DIR, DT/DIS Max. voltage range at ERx Max. voltage range at INH Max. voltage range at BHx Max. voltage range at DHx2 Max. voltage range at GHx3 Max. voltage range at SHx3 Max. voltage range at GLx Max. voltage range at DLx Max. voltage difference BHx - SHx Max. voltage difference Gxx - Sxx Power dissipation (DC) @ TA=125C / min.footprint Power dissipation (DC) @ TA=85C / min.footprint Electrostatic discharge voltage (Human Body Model) according to MIL STD 883D, method 3015.7 and EOS/ESD assn. standard S5.1 - 1993 Jedec Level Thermal resistance junction - ambient (minimal footprint with thermal vias) Thermal resistance junction - ambient (6 cm2) Functional range Parameter and Conditions
at Tj = -40...+150C, unless otherwise specified
Symbol VS Tj Tstg
VINH VBHx VDHx VGHx VSHx VGLx VDLx VBHx-VSHx VGxx-VSxx Ptot Ptot VESD4
Limits Values Min. Max. -4 60 -40 150 -55 150 -1 6 -0.3 6 -0.6 60 -0.3 90 -4 75 -6.8 86 -6.8 75 -2 12 -2 75 -0.3 17 -0.3 11 0.33 0.85 2
Unit V C V V V V V V V V V V V W W kV
3 RthJA RthJA 75 75 K/W K/W
Symbol
Values min max 7.5 -40 -0.3 -0.3 -0.6 -0.3 -4 60 150 5.5 5.5 60 90 75
Unit
Supply voltage Operating temperature range Max. voltage range at PWM, DIR, DT/DIS Max. voltage range at ERx Max. voltage range at INH Max. voltage range at BHx Max. voltage range at DHx2
1 2
VS Tj
VINH VBHx VDHx
V C V V V V V
With external resistor (10 ) and capacitor The min value -4V is reduced to -( VBHx - VSHx) in case of bootstrap voltages VBHx-VSHx <4V 3 The min value -7V is reduced to -(VBHx - VSHx - 1V) in case of bootstrap voltages VBHx-VSHx <8V 4 All test involving Gxx pins VESD=1 kV!
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Data Sheet TLE6284G
Max. voltage range at GHx3 Max. voltage range at SHx3 Max. voltage range at GLx Max. voltage range at DLx Max. voltage difference BHx - SHx Max. voltage difference Gxx - Sxx PWM frequency Minimum on time external lowside switch - static condition @ 20 kHz; QGate = 200nC VGHx VSHx VGLx VDLx VBHx-VSHx VGxx-VSxx FPWM tp(min) -6.8 -6.8 -2 -2 -0.3 -0.3 0 86 75 12 75 12 11 50 2 V V V V V V kHz s
Electrical Characteristics
Parameter and Conditions
at Tj = -40...150C, unless otherwise specified and supply voltage range VS = 7.5 ... 60V; fPWM = 20kHz
Symbol
Values min typ max
Unit
Static Characteristics Low level output voltage (VGSxx) @ I=10mA High level output voltage (VGSxx) @ I=-10mA Supply current at VS (device disabled) @ Vbat= VS =14V RDT=400k Supply current at VS (device disabled) @ Vbat= VS =42V RDT=400k Quiescent current at VS (device inhibited) @ Vbat= VS =14V RDT=400k RSCD1+RSCD2 = RSCD3+RSCD4 =12k Quiescent current at VS (device inhibited) @ Vbat= VS =42V RDT=400k RSCD1+RSCD2 = RSCD3+RSCD4 =12k Supply current at VS @ Vbat= VS =14V, fPWM = 20kHz (Outputs open) Supply current at VS @ Vbat= VS =14V, fPWM = 50kHz (Outputs open) Supply current at VS @ Vbat= VS =42V, fPWM = 20kHz (Outputs open) Low level input voltage High level input voltage Input hysteresis Inhibit trip level
VLL VHL
IVS(dis)14V IVS(dis)42V IVS(inh)14V
-8 ----
60 10 4 4 0.6
150 11 8 8 1.5
mV V mA mA mA
IVS(inh)42V
--
0.6
1.5
mA
IVS(open)14V IVS(open)14V IVS(open)42V VIN(LL) VIN(HL)
----2.0 100 1.3
7 7 7 --170 2
15 15 15 1.0 -3
mA mA mA V V mV V
VIN
VINH
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Data Sheet TLE6284G
Dynamic characteristics (pls. see test circuit and timing diagram) Turn on current @ VGxx -VSxx = 0V; Tj=25C @ VGxx -VSxx = 4V; Tj=125C @ CLoad=22nF ; Rload= 0 Turn off current @ VGxx -VSxx = 10V; Tj=25C @ VGxx -VSxx = 4V; Tj=125C @ CLoad= 22nF ; Rload=0 Dead time (adjustable) @ RDT = 1 k @ RDT = 10 k @ RDT = 50 k @ RDT = 200 k @ CLoad=10nF ; Rload=1 Rise time @ CLoad=10nF ; Rload=1 (20% to 80%) Fall time @ CLoad=10nF ; Rload=1 (80% to 20%) Disable propagation time @ CLoad=10nF ; Rload=1 Reset time of diagnosis @ CLoad=10nF ; Rload=1 Input propagation time (low side turns on, 0% to 10%) Input propagation time (low side turns off, 100% to 90%) Input propagation time (high side turns on, 0% to 10%) Input propagation time (high side turns off, 100% to 90%) Input propagation time difference (all channels turn on) Input propagation time difference (all channels turn off) Input propagation time difference (one channel; low on - high off) Input propagation time difference (one channel; high on - low off) Input propagation time difference (all channels; low on - high off) Input propagation time difference (all channels; high on - low off) IGxx(on) -----0.05 0.40 ---3.6 1 ----20 -----850 700 580 300 0.01 0.20 1.0 3.1 100 150 5 2 250 110 200 130 50 25 120 100 120 100 -----0.38 2.50 -300 440 7 3.1 500 500 500 500 70 50 180 180 180 180 mA
IGxx(off)
mA
tDT
s
t rise tfall tP(DIS) tP(CL) tP(ILN) tP(ILF) tP(IHN) tP(IHF) tP(Diff) tP(Diff) tP(Diff) tP(Diff) tP(Diff) tP(Diff)
ns ns s s ns ns ns ns ns ns ns ns ns ns
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Data Sheet TLE6284G
Test Circuit and Timing Diagram
PWM
x2
PWM GHx
Rload = 1 Ohm Cload = 10 nF
SHx
50%
VGHX_C
tP(IHN) trise
GLx
tP(IHF) tfall
t
90%
Rload = 1 Ohm Cload = 10 nF
SLx
VGHX_C
VGLX_C
80%
20% 10%
t
tP(ILF) tfall tP(ILN) trise
Test Conditions :
Junction temperature Tj = -40 ... 150oC Supply voltage range Vs = 7.5 ... 60V PWM frequency fPWM = 20 kHz
VGLX_C
90% 80%
20%
10%
t
TJ(OV) TJ(OV) tSCP(off) VDS(SCP) 150 6 0.5 0.45 3.3 -170 20 9 0.75 0.75 3.7 180 -3.7 4.8 190 12 1.0 1.05 4.0 1.0 4.6 5.9 C C s V V mV V V V
Diagnosis and Protection Functions Overtemperature warning Hysteresis for overtemperature warning Short circuit protection filter time Short circuit criteria (VDS of Mosfets) For Low sides For High sides Disable input level Disable input hysteresis Error level @ 1.6mA IERx Under voltage lock out for highside output - bootstrap voltage Under voltage lock out for lowside output - supply voltage
VDIS VDIS VERx VBHx (uvlo) VVs (uvlo)
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Data Sheet TLE6284G
Remarks: Default status of input pins: To assure a defined status of the logic input pins in case of disconnection, these pins are internally secured by pull up / pull down current sources with approx. 20A. The high voltage proof input INH should be secured by an external pull down resistor close to the device. The following table shows the default status of the logic input pins. Input pin PWM and DIR DT/DIS (active high) Default status Low (= break in high side) High
Definition: In this datasheet a duty cycle of 98% means that the GLx pin is 2% of the PWM period in high condition. Remark: Please consider the influence of the dead time and the propagation time differences for the input duty cycle
Functional description
Description of Dead Time Pin / Disable Pin / Reset This pin allows to adjust the internal generated dead time. The dead time protects the external highside and lowside Mosfets in the same halfbridge against a lowohmic connection between battery and GND and the resulting cross current through these Mosfets. The adjustable dead time allows to minimize the power dissipation caused by the current flowing through the body diode during switching the halfbridge. In addition this pin allows to reset the diagnosis registers without shut down of any output stage as well as the possibility to shut down all outputs simultaneously. Condition of DT/DIS pin 0 - 3.5V > 4V Function Adjust dead time between 10ns and 3.1s a) Reset of diagnosis register if DT/DIS voltage is higher than 4V for a time between 3.1s and 3.6s b) Shut down of output stages if DT/DIS voltage is higher than 4V for a time above 7s (Active pull down of gate voltage)
Description of Inhibit functionality In automotive applications which are permanently connected to the battery line, it is very important to reduce the current consumption of the single devices. Therefore the TLE6284G offers a inhibit mode to put the device to sleep and asure very low quiescent currents. To deactivate the inhibit mode the INH pin has to be set to high. This can be done by connecting this pin to voltages between 3.3 and 60V without external protection. An inhibit mode means a complete reinitialisation of the device. Description of Diagnosis The two ERx pins are open collector outputs and have to be pulled up with external pull up resitors to 5V. In normal conditions both ERx signals are high. In case of shutdown of any output stage the ER1 is pulled down. This shut down can be caused by undervoltage or short circuit. In this condition ER2 indicates the reason for the shut down. 8 2006-01-30
Data Sheet TLE6284G
Condition of ER1 pin 5V 5V 0V 0V Condition of ER2 pin 5V 0V 5V 0V Function no errors overtemperature warning of driver IC Shut down of any output stage caused by short circuit Shut down of any output stage caused by undervoltage
Recommended Start-up procedure The following procedure is recommended whenever the Driver IC is powered up: * * * * Disable the Driver IC via DT/DIS pin Wait until the bootstrap capacitors of High Side MOSFET CBx are charged (the waiting time depends on application conditions, e.g. CBx and RBx) Enable the Driver IC via DT/DIS pin Start the operation by applying the desired pulse patterns. Do not apply any pulse patterns to the PWM or DIR pin, before the CBx capacitors are charged up.
Short Circuit protection The current threshold limit to activate the Short Circuit protection function can be adjusted to larger values, it can not be adjusted to lower values. This can be done by external resistors to form voltage deviders across the "sense element" (pls. see Application block diagram on pg. 2), consisting of the Drain-Source-Terminals, a fraction of the PCB trace and - in some cases - current sense resistors (used by the C not by the Driver IC). The Short Circuit protection can be disabled for the High Side MOSFETs by shorting DH1 with SH1 and DH2 with SH2 on the PCB; in this case the DHx pins may not be connected to the Drains of the associated MOSFETs. To disable Short Circuit protection for the Low Side MOSFETs the DL1 and DL2 pin should be connected to the Driver ICs Ground. Shut down of the driver A shut down can be caused by undervoltage or short circuit. A short circuit will shut down only the affected Mosfet until a reset of the error register by a disable of the driver occurs. A shut down due to short circuit will occur only when the Short Circuit criteria VDS(SCP) is met for a duration equal to or longer than the Short Circuit filter time tSCP(off). Yet, the exposure to or above VDS(SCP) is not counted or accumulated. Hence, repetitive Short Circuit conditions shorter than tscp(off) will not result in a shut down of the affected MOSFET. An undervoltage shut down shuts only the affected output down. The affected output will auto restart after the undervoltage situation is over. Operation at Vs<12V If Vs<11.5V the gate voltage will not reach 10V. It will reach approx Vs-1.5V, dependant on duty cyle, bootstrap capacitor, total gate charge of the external Mosfet and switching frequency. Operation at different voltages for Vs, DH1 and DH2 If DH1 and DH2 are used with a voltage higher than Vs, a duty cycle of 100% can not be guaranteed. In this case the driver is acting like a normal driver IC based on the bootstrap principle. This means that after a maximum "On" time of the highside switch of more than 1ms a refresh pulse to charge the bootstrap capacitor of about 1s is needed to avoid undervoltage lock out of this output stage. 9 2006-01-30
Data Sheet TLE6284G
Operation at extreme duty cycle: The integrated charge pump allows an operation at 100% duty cycle. The charge pump is strong enough to replace leakage currents during "on"-phase of the highside switch. The gate charge for fast switching of the highside switches is supplied by the bootstrap capacitors. This means, that the bootstrap capacitor needs a minimum charging time of about 1ms, if the highside switch is operated in PWM mode (e.g. with 20kHz a maximum duty cycle of 96% can be reached). The exact value for the upper limit is given by the RC time formed by the impedance of the internal bootstrap diode and the capacitor formed by the external Mosfet (CMosfet=QGate / VGS). The size of the bootstrap capacitor has to be adapted to the external MOSFET the driver IC has to drive. Usually the bootstrap capacitor is about 10-20 times bigger then CMosfet. External components at the Vs Pin have to be considered, too. The charge pump is active when the highside switch is "ON" and the voltage level at the SHx is higher than 4V. Only under these conditions the bootstrap capacitor is charged by the charge pump. Estimation of power loss within the Driver IC The power loss within the Driver IC is strongly dependent on the use of the driver and the external components. Nevertheless a rough estimation of the worst case power loss is possible. Worst case calculation is: PLoss = (Qgate*n*const* fPWM + IVS(open)/20kHz)* VVs - PRGate With: PLoss = Power loss within the Driver IC fPWM = Switching freqency Qgate = Total gate charge of used MOSFETs at 10V VGS n = Number of switched MOSFETs const = Constant considering some leakage current in the driver (about 1.2) IVS(open) = Current consumption of driver without connected Mosfets during switching VVS = Voltage at Vs PRGate = Power dissipation in the external gate resistors This value can be reduced dramatically by usage of external gate resistors.
Estimated Power Loss PLOSS within the Driver IC for different supply voltages Vs at QG = 100nC @ VGS = 10V 0,8 0,7 0,6 PLOSS (W) 0,5 0,4 0,3 0,2 0,1 0 0 10 20 30 40 50 60 PWM Frequency (kHz)
Vs = 8V
Estimated Power Loss PLOSS within the Driver IC for different gate charges QG at supply voltage Vs = 14V 0,8 0,7 PLOSS (W) 0,6 0,5 0,4 0,3 0,2 0,1 0 0 10 20 30 40 50 60 PWM Frequency (kHz)
QG = 50nC QG = 100nC QG = 200nC
Vs = 14V Vs = 18V
Conditions : Junction temperature Tj = 25oC Number of switched MOSFET n = 2 Power dissipation in the external gate resistors PRGate = 0,2*PLoss
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Data Sheet TLE6284G
Gate Drive characteristics
VPWM_HS BHx
Logic + Level Shift + VGS limit + Under voltage
Vs
SCD
iGxx(on) iGxx(off)
DHx CB GHx iGHx
iGxx(on)
850 mA Peak
VPWM_HS
iGxx(off)
580 mA Peak
SHx
Motor iGHx
TLE6284G High Side Driver
Test Conditions : - Turn On : VGS = 0V, Tj = 25oC - Turn Off : VGS = 10V, Tj = 25oC
This figure represents the simplified internal circuit of one high side gate drive. The drive circuit of the low sides look similar.
This figure illustrates typical voltage and current waveforms of the high side gate drive; the associated waveforms of the low side drives look similar.
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Data Sheet TLE6284G
Truth Table Input DIR PWM 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 X X 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 X X DT / DIS <3.5V <3.5V <3.5V <3.5V <3.5V <3.5V <3.5V <3.5V <3.5V <3.5V <3.5V <3.5V <3.5V <3.5V <3.5V <3.5V X >4V Conditions UV 0 0 0 0 1 1 1 1 0 0 0 0 0 0 0 0 X X OT 0 0 0 0 0 0 0 0 1 1 1 1 0 0 0 0 X X SC 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 X X Output driver IC GH GL GH GL ER ER 1 1 2 2 1 2 1 0 0 1 5V 5V 1 0 1 0 5V 5V 0 1 1 0 5V 5V 1 B B 0 B 1 1 0 1 E E 0 E 0 0 0 0 0 B 0 0 0 1 0 0 0 E 0 0 0 1 0 B B B 0 1 1 1 0 E E E 0 0 0 B 0 0 0 1 0 0 0 E 0 0 0 0 0 5V C C C C 5V 5V 5V 5V F F F F 5V 5V 5V D D D D 0V 0V 0V 0V 5V 5V 5V 5V 5V 5V Output Bridge Out1 Out2 1 1 0 1 1 1 1 1 1 0 1 1A 1A 0A 1A T T
A A
0 1 1 1 0A 1A 1A 1 0 1 1 1 0A 1A 1A 1A T T
A
0A
A
A) Tristate when affected by undervoltage shut down or short circuit B) 0 when affected; 1 when not affected; self recovery C) 0V when output does not correspond to input patterns; 5V when output corresponds to input patterns D) Is an output affected by undervoltage ER2 is 0V E) 0 when affected- the outputs of the affected halfbridge are shut down and stay latched until reset; 1 when not affected F) 0V when output does not correspond to input patterns - the outputs of the affected halfbridge are shut down and stay latched until reset; 5V when output corresponds to input patterns. T) Tristate X) Condition has no influence Remark: To generate fast decay control mode, set PWM to 1 and send pwm-pattern to DIR input.
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Driving Sequence and current flow in the MOSFETs and the motor
PWM t
DIR t
VGH1
t
VGH2 t
VGL1 t
13
Motor turns right Motor stops
Vs Vs Vs Vs
VGL2 t Motor turns left Motor stops t
Acceleration
Imotor
Vs
Vs
M
M M
M
M
M
Data Sheet TLE6284G
2006-01-30
Data Sheet TLE6284G Package and Ordering Code
(all dimensions in mm)5
Package Code
P-DSO 20
5
For detailed information about packages please contact http://www.infineon.com/cgi/ecrm.dll/ecrm/scripts/pack_cat.jsp?oid=-8781
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Data Sheet TLE6284G
Published by Infineon Technologies AG, Bereich Kommunikation St.-Martin-Strasse 53, D-81541 Munchen (c) Infineon Technologies AG 1999 All Rights Reserved. Attention please! The information herein is given to describe certain components and shall not be considered as warranted characteristics. Terms of delivery and rights to technical change reserved. We hereby disclaim any and all warranties, including but not limited to warranties of non-infringement, regarding circuits, descriptions and charts stated herein. Infineon Technologies is an approved CECC manufacturer. Information For further information on technology, delivery terms and conditions and prices please contact your nearest Infineon Technologies Office in Germany or our Infineon Technologies Representatives worldwide (see address list). Warnings Due to technical requirements components may contain dangerous substances. For information on the types in question please contact your nearest Infineon Technologies Office. Infineon Technologies Components may only be used in life-support devices or systems with the express written approval of Infineon Technologies, if a failure of such components can reasonably be expected to cause the failure of that life-support device or system, or to affect the safety or effectiveness of that device or system. Life support devices or systems are intended to be implanted in the human body, or to support and/or maintain and sustain and/or protect human life. If they fail, it is reasonable to assume that the health of the user or other persons may be endangered.
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